Category: Garden

Posts about gardening and related topics, such as canning and maybe other aspects of food preservation.

Post G23-046: Winnowing seed and making mustard

Bottom line:  A weak little computer fan is just right for winnowing mustard seed.  Optionally, roll the seeds down a tray to separate out the last little bits of chaff.

After cleaning some mustard seed in that fashion, I ground it in a cheap spice/coffee grinder, then used a recipe that promised to produce something like French’s yellow mustard.

I achieved neither the color nor the consistency of French’s.  But I think it’s recognizably mustard.

I’ll need to wait a few days for the taste test.

At the very least, this went a lot better than last year.  A box fan is way too large, and way to strong, for winnowing tiny mustard seeds.

Details follow.  See also:

Post G23-043: Threshing mustard by combing it.

Continue reading Post G23-046: Winnowing seed and making mustard

Post G23-043: Threshing mustard by combing it.

 

I threshed and rough-cleaned my first batch of mustard today.  Took about an hour.  Yield was poor.  Worse, the seeds look like last year — a mix of yellow mature seed and green/black immature seed.

Not clear what I’m going to do next, but I can endorse one method for threshing a stack of dried mustard plants reasonably efficiently:  Comb them to break open the seed pods. Continue reading Post G23-043: Threshing mustard by combing it.

Post G23-042: Harlequin bugs on my cut mustard.

Source: NCSU state cooperative service.

This is an observation on the harlequin bug.  Same size and shape as a stink bug, but gaudy.  They are piercing-sucking insects, and they are a pest of brassicas.  That category includes mustard.

I have them in my garden for the first time ever.

To cut to the chase:  I believe the harlequin bug is attracted to the cut (but still living) stems of my mustard plants.

So if you cut your mustard while it’s still slightly green, or your mustard plants vary greatly in maturity at time of harvest, any still-living stubble from that cutting may attract the harlequin bug.

This is plausible. at least.  These bugs are, in fact, sap-suckers.  I’m just saying that it appears they were drawn by the smell of the raw cut green stem ends.

This is my one experience with these, so who knows.  I present the evidence as follows:

  1. I grew a lot of mustard last year, and I never saw these.
  2. But last year, I let the mustard go completely dry before I cut it.
  3. I grew a lot of mustard this year as well, and I never saw these.
  4. Then I cut a third of my plants down on 7/9/2023, or four days ago.
  5. As directed, I tried to cut them just below where the seed pods form.
  6. The lower portions of a fair number of the larger pants survived.
  7. Less than four days later, those bugs were all over a handful of large cut stems.
  8. But there were none in the (much larger) beds of mustard were still uncut.

So, grow it and cut it down dry?  No H-bugs.  Grow it again.  Still no H-bugs.  Cut it down green?  Four days later, and I’m infested.  But only where those green cut stems are.

Maybe that’s all coincidence.  I think not.

I’m just getting it down in writing.  I don’t see this being said elsewhere on the internet.

G23-041: No-dig potatoes in leaf mulch. Poor yield.

 

This is just a note in another garden failure.  I won’t be trying no-dig potatoes in leaf mulch again.  I’m going back to planting potatoes in dirt.

Edit 2/10/2024:  After seeing a near-identical failure on YouTube, by master gardener Mark Valencia (Self-Sufficient Me), I’m pretty sure that the problem was heat.  Potatoes do not like heat, and excessively warm soil produces few, small, knobby potatoes.  That describes his yield and my yield, despite the fact that his pests, soil, leaf mulch and potato varieties have nothing in common with mine.  (I am in Virginia USA and he’s in Queensland Australia.) What we have in common is a hot climate.  Too hot for potatoes at mid-summer, in both places.  I’m guessing that a thin layer of dark leaf mulch, plus Virginia/Australia sunshine, allowed the tubers to get too warm.  I also note in passing that Ruth Stout — the U.S. popularizer of no-dig gardening — was a New Englander.   

The failure in brief

This year I tried growing no-dig potatoes using leaf mulch.  Three varieties, planted with minimal effort and zero forethought, on 3/17/2023 (Post G23-016).

The russets were a near-total failure.  Lucky if I managed to get back the three pounds I used as seed potatoes.  But russets basically won’t grow in the South, owing to their need for a long growing season.  So that was no particular test of no-dig using leaf mulch.

I dug up the rest of my potatoes this morning — reds and golds — and the results weren’t much better.  I’m guessing from six pounds of potatoes planted, I might have gotten 15 pounds of potatoes back.  Almost all are small.  Many are misshapen.  I suspect some of those are going to be unusable.

Tellingly:

  • The leaf mulch had shrunk down to about 3″ in most places
  • There were only two full-sized potatoes.
    • Both had dug themselves into the ground.
  • Several potatoes had rotted.
  • Several were misshapen.
  • Several had visible insect damage.
  • There was considerable insect activity in the leaf mulch.
  • The potatoes were as dirty as if they’d been grown in dirt, to boot.

My conclusion is that, for a lot of reasons, my local municipal leaf compost is not a good medium for growing potatoes.

By contrast, growing no-dig potatoes in straw, two years ago, worked reasonably well.  Yield was less than for potatoes grown in dirt (which I think is an established fact).  But I got a good lot of full-sized, good-looking, clean potatoes (see Post G21-052 for details).

If it were not for the cost of straw bales in this area, I’d go back to growing no-dig potatoes in straw.  As it stands, I’ll be going back to growing potatoes in dirt.  I’m not going to try leaf mulch again.

Post G23-040: Radiative cooling experiment, a puzzling worse-than-total-failure.

 

This is a simple controlled trial of whether I can get a few degrees F of “radiative cooling” in my raised beds, using radiant barrier.  See a few posts back for details.

In a nutshell, total failure.  And I have no clear idea why.

Continue reading Post G23-040: Radiative cooling experiment, a puzzling worse-than-total-failure.

Post G23-039: Eats, shoots, and leaves. When to harvest mustard, decoded.

 

I’ve been having a hard time determining when and how to harvest mustard.  Seems like mine goes from green, to shattered (broken, empty pods), with nothing in-between. If I follow typical internet garden advice and let it stand until its completely dry, I’m not going to have any seeds left.

To hedge my bets, I cut down about a third of my plot of mustard a few days back.  It’s now drying in the sun.  But from the looks of it, above, I may have been too early.  That still looks awfully green.

The best description I found of what I’m supposed to be looking for, if I want to “swath” my mustard (cut it before it’s fully dry), is from North Dakota State University

Mustard should be swathed following general leaf drop when overall field color changes from green to yellow/brown and early enough to avoid shattering.

To determine physiological maturity, select pods from the middle of the racemes of several plants in areas representing the average maturity of the field. Most varieties are at the optimum maturity for swathing when upper pods have turned and seeds are brown or yellow. The remaining 25% of green seeds will mature in the swath prior to harvest.

Much of that makes sense.  Look for leaf drop.  Got it.  Look for the field turning from green to gold.  Fine.  Now check a bunch of pods that represent the median of what’s in your field.  That is, seed pods in the middle of the stem, on plants of average maturity.

Then I lost it.  I could not make head or tail out of this phrase:

” … when upper pods have turned and seeds are brown or yellow.”

But, on mine, the pods at the bottom turn brown first.  Which makes sense, because those would be the first to flower.  If I wait for all the upper pods to turn (from green to gold), I won’t have any seeds left.  And since this description was written for the types of mustard that shatter easily, I know that’s not what it’s telling me to do.

After about my twentieth re-reading, I finally got it. 

Not “upper pods” meaning the ones at the top of the plant.  “Upper pods”, meaning, for the test pods, the end of the pod that attaches to the plant.  That end of the median pod should be golden.  It’s OK if the rest of the pod is green, as long as the seeds are fully-formed, and most (75%) are brown.

Re-written:  Harvest when the median pod, on the median plant, is starting to turn golden, at the stem end of the seed pod.  And when, after splitting the seed pod, most of the seeds in the pod are golden.  At that stage, as long as the rest of the seeds in the pod are fully formed, they’ll turn from green to golden as the plant cures.

Below I have a seed pod that’s almost right.  The upper pod — the part attached to the stem — is brown.  The tip is still green.  And, while you can’t see it, the first couple of seeds in the pod were, in fact, yellow.  And all the seeds are fully-formed, that is, full size.  That should mean that all the green seeds shown here would have gone on to ripen to gold, if I’d cut that plant down at this stage.

That’s still a bit too young, from the criteria above.  I ought to see yellow seeds down most of the pod.  But even at this stage, the pod was already starting to shatter (separate).  So it’s possible that I have to harvest at this relatively green state, and hope for the best.

Conclusion

I think this all fits now.

If you have a mustard that doesn’t shatter, you can just wait until the whole field turns brown, and harvest it.

If you have one that shatters — where the seed pods split once they turn brown, as mine has been doing — you can’t wait that long.

Instead, you’re going to have to harvest it partly green.  That inevitably means harvesting seed pods that are in a wide range of maturities.

Determining what “partly” means is the tricky part.  So you pick the point at which the median seed pod in your field is just ripe enough that it will continue to ripen after you cut it.  That means that the top (stem end) of that pod is brown, and most (but not all) the seeds in those median pods have already turned brown.

Post G23-038: Tomato non-ripening and a radiative cooling experiment.

 

Non-ripening tomatoes and nighttime temperatures

In 2020, we had an extended period when tomatoes would not ripen.  That was new to me, but apparently that’s pretty common in the South.  The lack of ripening is due to excess heat.  But it’s not a daytime excess.  It’s due to warm nights, as many varieties of tomatoes will not begin the ripening process (enter the “breakers” stage) if nighttime temperatures consistently exceed 70 or maybe 72 F.  See Post #G22-43 for full details.

Source:  Calculated from historical weather data from NOAA, for Dulles International Airport.

As explained in that prior post, the non-ripening is a subtle thing.  Tomatoes that have already begun the ripening process will continue to ripen.  But those that have not yet started that will remain green.  So, at some ill-defined lag after the nights warm up, the supply of ripe tomatoes gradually dries up.

That “warm nights” thing is a pity, because climate models have long predicted that global warming will raise nighttime temperatures more than daytime temperatures.  So it would seem that warmer nights are in the pipeline.

If you look at the graph above, that 2020 stretch of warm nights began in the middle of July. 

Here’s the extended forecast for Vienna VA today:

It’s worth pointing out two things.

First, we’re surely in for at least a few nights above 70F.  And, depending on whom you believe (and your misplaced trust in 10-day forecasts), we might be in for an extended period with nighttime temperatures over 70F.

Second, it won’t take one whole lot of warming to push all those forecasts above the 70F threshold.  That’s going to make it tough to grow a whole lot of varieties of tomatoes around here, I think.  But we’re likely talking the better part of a century from now.  I hope.

Everybody talks about the weather, but nobody does anything about it:  Radiative cooling.

Not me.  I’m going to try a radiative cooling experiment.  I’m going to see if I can use radiant barrier to reduce the nighttime temperature in parts of my garden.

It’s an unusual idea, but it’s not rocket science.

As I noted in earlier posts on this topic (G21-014 ,  G21-015 ,  G22-005 , etc.) a garden bed is like a big window, looking straight up into outer space.  As such, it continuously radiates heat energy (long-wave infrared) upward, toward the cold of outer space.  By my calculation, on a cold spring night, you lose more heat from radiation than from conduction.

That’s why a radiant barrier is what you want, for frost protection, for your garden beds.  That can be a space blanket or similar material.  But that’s also why a glass cloche works to prevent freezing overnight.  And why a simple, thin-walled glass mason jar provides excellent frost protection for tender plants (Post G22-006).  And, by contrast, why polyethylene sheeting does diddly-squat to prevent overnight freezing (G22-005).

But, weirdly enough, you can also use a radiant barrier for cooling, by preventing ambient radiation from reaching your garden bed at night.  In effect, you make it so that your garden bed “sees” only the cold of outer space, directly over head.  If the air is sufficiently transparent to long-wave infrared, your garden bed then cheerfully radiates energy off into outer space, and cools as a consequence.

This technique works OK in the dry desert, with a clear sky, which may explain in part why various Middle Eastern cultures have used it for millennia, to make small amounts of ice, in the desert (reference).  That said, even under those optimal conditions, temperatures had to be near-freezing to start with.  This reference suggest an upper limit of 5 C, or about 41 F.  Ideally, a combination of insulation, evaporative heat transfer, and radiative losses would generate small amounts of ice, under those conditions.

By contrast, the main problem with using that here is water.  Water vapor is the most important greenhouse gas.  It’s plentiful in the atmosphere, and it absorbs and re-emits infrared across many parts of the infrared spectrum.  Between the humidity and the clouds, a lot of what gets radiated into space will be, in effect, reflected (re-emitted) right back down to earth.

Which is, in a nutshell, the greenhouse effect.

OTOH, I only need a few degrees.  If this can pull a 9F differential in the dry desert, maybe it can drop the temperature 3F on a cloudless Virginia summer night.  After all, I’m just trying to trick those tomatoes into starting the ripening process.  My understanding is, once that gets going, they will continue to ripen.

So it’s worth a shot, just out of intellectual curiosity.  I’m going to set up a small enclosure made of radiant barrier — basically, a big tube with the open ends facing ground and sky.  Cap that with a piece of clear polyethylene sheet to provide an IR-transparent barrier to the outside air.  Then use temperature loggers to track nighttime temperatures inside and outside the enclosure.   I might get lucky.

Otherwise …

The nice thing about this method is that there’s zero energy consumption.

Probably ought to consider a shade cloth, as well, but I can’t quite figure out how that would be much help in terms of nighttime temperatures.  Plausibly, the cooler the soil stays during the day, the cooler the area may be at night.

But if I’m willing to expend a bit of energy, I think a mist-cooling device would plausible achieve a sufficient drop in temperature.  Mist coolers work by converting sensible heat (temperature) into latent heat (water vapor, instead of liquid water).  I went over that in my post on the true energy cost of humidifiers, Post #1669.

That said, bathing my plants in mist all night just seems like a recipe for every tomato leaf disease known to mankind.  So that’ll only be used as a last resort.

Otherwise, short of sticking a window AC under a tarp, and using that, I guess I’m at the mercy of Mother Nature here. If it’s too hot to ripen tomatoes, then it’s too hot to ripen tomatoes.  Grow something else for the time being.

Any sufficiently advanced technology is indistinguishable from magic.  (Arthur C. Clarke)

My garden beds emit “black body” radiation.  That is, they toss out radiation at every frequency, with a peak in the long infrared.  As a consequence, some of that is bound to be absorbed and re-emitted by atmospheric gasses.

But suppose, through some miracle of modern science, you could create a material that radiates infrared only on those bands of frequencies where the atmosphere is transparent to infrared.  That is, frequencies that aren’t absorbed and re-emitted by common atmospheric greenhouse gasses.

Then — and frankly, this is where I lose it — you could, in theory, create a material that would literally cool itself below ambient temperature.  If the air outside is 80F, your miracle-o’-modern-science could be 78F, with no power input.  Just from enhanced “emissivity” in the right part of the spectrum.

Or, as these folks put it, emphasis mine:

... the PDRC coating demands a significant solar reflectance (Rsolar) in the spectral region (0.3–2.5 m) and a significant thermal emissivity (LWIR) in the environmental long-wave infrared (LWIR) propagation region (8– 13 m). As a result, during the day, the energy loss to frigid space ... is far more than the warming from daylight, resulting in electricity-free spontaneous refrigeration.

In other words, you could sit a piece of this stuff out in the sunshine, and it would remain cooler than the ambient air.  With no energy input.

That’s close enough to magic for me.

G23-037: Eastern Boxelder Bug.

 

Another gardening year, another invasive pest.

This year, I’ve seen a few cucumber beetles and a few Japanese beetles.  And that’s about it, for garden pests.  In particular, I haven’t seen a squash vine borer.  Then again, I gave up on planting summer squash.  Due to the squash vine borer.

And then there’s this thing, above.  This, by contrast, seems to be all over my garden this year, chowing down on a wide variety of plants.

Based on Google image search, this is a nymph (immature stage) of the Eastern Boxelder Bug, Jadera haematoloma.

Which is a bit odd, really.  Apart from never having seen this one before.

There are no boxelders near here.  At least, none that I have ever noticed.  And I do notice them, because the leaves of the boxelder are a dead ringer for poison ivy.  Having grown up roaming fields and woods in Virginia, poison ivy is one of those things that’s now hard-wired in my brain.

But as an alternative host, they like silver maples, and those we have in abundance.  Some very large silver maples have been in the process of dying off, a few hundred feet up the road from me, and I wonder if that has displaced some population of eastern boxelder bugs.

At any rate, the consensus of opinion is that these are mostly harmless.  They feed by piercing and sucking, but nobody seems to suggest that they do a lot of damage to garden plants.  And, unlike hard-shelled beetles, these are easily killed by a simple soap-and-water spray.  So if they get out of hand, there is (at least in theory) an easy control measure.

So, for once, I’ll go the live-and-let-live route, for this latest garden pest.  At least it’s a native species, and at least it doesn’t normally cause much damage.